The invention relates to a portable, electric air humidifier, more particularly to an improved warm-air humidifier.
Air humidifiers have been found to be important in controlling the environment in homes during very dry weather, or in winter whenever outside air of low temperature is drawn inside and heated, causing the relative humidity in the home to be lowered to an uncomfortable degree.
Portable humidifiers are well known in the art, and may be classified as follows:
1. Steam generators which comprise a water container and an electric heating element submerged in the water, there being provided safety devices for switching off the current as soon as the water level drops below the heating element. A flow of hot steam is blown directly into the room to be humidified and there is always the danger of a person, especially a child, being scalded whenever he comes into contact with the jet of steam ejected at a temperature of 212.degree. F. Furthermore, the container of hot water, when overturned, may cause serious injuries to the person nearby.
2. Porous medium humidifiers generally include a porous medium structure partly submerged in cold water contained in an open vessel and a blower unit drawing air through the porous medium structure. The porous medium is either in the shape of a disc or a drum with part of the medium dipping into the water, which is slowly rotated while air is blown through the portion above the water level, thus carrying humidity into the room; or it is in the form of a stationary body adapted to draw water into the upper non-immersed part by capillary action, from where it is carried into the room by air blown therethrough.
3. Ultra-sonic humidifiers generally comprise a container filled with water which is brought to vibration by high-frequency vibrator means which causes the water to be atomized. An air stream directed onto the water surface carries the mist into the room to be humidified.
The major drawback of both the two latter appliances is the fact that the water staying in the container is not heated to boiling point as in the steam generator and, therefore, is susceptible to the growth of microorganisms which are subsequently carried by the air stream into the room and ingested by the people staying there.
4. Warm-air humidifiers share the benefits of steam generators in that growth of micro-organisms is forestalled by heating the water to boiling point. Also, warm-air humidifiers avoid the drawback of hot steam entering the room, since in this type of humidifier the steam is carried into the room as a mist mixed with air, at a temperature to be selected by judiciously choosing the ratio of steam and air.
A typical warm-air humidifier is described in U.S. Pat. No. 4,564,746: it includes a heated evaporation chamber which is enclosed to prevent leakage or damage, and a fan adapted for dispersing the generated steam into the room via a cabinet passageway. The evaporation chamber is mounted on tracks which permit its sliding out of its enclosure and is thus easily accessible for cleaning and servicing. The heating element which is operationally enclosed in the chamber is attached to a cover which is likewise movable out of the humidifier cabinet for cleaning and servicing.
The drawback of this humidifier is its relatively intricate and expensive design: according to the description, the heating element is attached to a movable cover which is provided with flexible tubing and must be moved upwards on vertical tracks in order to clear the top of the water enclosure, permitting the latter to be slid out sideways. It requires a significant amount of space and cannot be serviced except by a skilled person.
It is, therefore, one object of the present invention to avoid the aforementioned drawbacks and to provide a portable room humidifier of simple design permitting its handling by any person having only a limited technical knowledge.
It is another object to provide a compact, portable appliance requiring a minimum of space, even while being opened for servicing and cleaning.
It is a further object to provide a humidifier which will operate at a moment's notice owing to a very small volume of water to be heated and brought to boiling point during the time it is in operation.
And it is still another object to provide a humidifier at low cost allowing its purchase and use by a majority of families.
These and other objects will be readily apparent from the following description of the invention and claims.